This application claims priority to European Application No. 00122993.9, filed Oct. 23, 2000, which is incorporated herein by reference.
1. Technical Field
The invention relates to a conditioning device for grinding wheels for machining the edge areas of plate-shaped objects, such as, for example, glass panes or the like, for which the grinding wheels, in a conditioned state, have at least one circumferential groove each which, at least in a partial section, tapers off towards the grinding wheel center.
2. Background Art
Bar-shaped conditioning devices are known in general practice and principally consist of a mineral material or materials having mineral components, the abrasive effect of which sets back the bond of the grinding wheel to be conditioned. The usual components of the material are, among others, aluminium oxide (corundum) and silicon carbide. The cross section is rectangular and the material properties are homogenous in the entire conditioning device.
The conditioned grinding wheel has a circumferential groove tapering off towards the grinding wheel center and of which the cross section has, in particular, a more or less semicircular form.
During the grinding operation of the edge areas of plate-shaped objects, such as, for example, the rounding of the edges of glass panes used in automobiles, the edge to be machined is at least brought to a convex curved form while, at the same time, the grinding wheel itself is subjected to a xe2x80x9cmachiningxe2x80x9d process due to wear caused by the machining of the edge areas of the glass panes so that the groove contour gradually resembles the contour of the unmachined edge areas of the glass panes and therefore needs to be conditioned.
By conditioning is basically understood to mean influencing of the sharpness of the grinding wheel surface including the groove surface, to maintain the groove contour for the longest possible time. In addition, by conditioning is also understood to indicate generation or restoring of a groove form, which has been used up or worn down or which has almost disappeared completely by numerous grinding operations.
As a result of the grinding operation of the edge areas, the corresponding grinding wheel surface cannot only become dull, but it can also be xe2x80x9cover-sharpenedxe2x80x9d, which is equally undesired. Both deviations from the normal, sharpened desired state can be eliminated by conditioning.
Conditioning by means of the aforementioned bar-shaped conditioning devices is achieved in that the conditioning device is provided with a profile adapted to the cross section of the groove to be achieved and brought into contact with the rotating grinding wheel with the result that the distribution of the sharpening effect over the entire groove form is uniform so that partial areas are either sharpened insufficiently or other partial areas are over-sharpened
As the contour of the conditioning device rapidly adapts to the contour of the groove so that the conditioning device has no more influence on the groove, it is general practice that the conditioning, especially the profiling, is usually carried out by cavity sinking with an electrode being profiled according to the groove form.
The disadvantage of this is that this method requires a complex and expensive eroding equipment so that the worn grinding wheels are usually sent away to the manufacturer or to another specialist for reconditioning. This in turn is a time consuming and expensive solution because it requires at least one spare grinding wheel to be available until the return of the conditioned grinding wheel. If several grinding machines and/or several differently profiled grinding wheels are concerned, this can involve quite an expensive stock-keeping.
The task of the invention is to avoid the aforementioned disadvantages and to provide a conditioning device for grinding wheels for machining the edge areas of plate-shaped objects, such as, for example, glass panes or the like, for which the grinding wheels, in a conditioned state, have at least one circumferential groove each which, at least in a partial section, tapers off towards the grinding wheel center, to permit the easy conditioning of these grinding wheels at any time and any place without expensive equipment. In such a way, a homogenous sharpness over the groove contour is achieved and both the profiling and the profile-maintaining sharpness influence are achieved in one operating cycle without disassembly of the grinding wheel.
This task is achieved by a conditioning device for grinding wheels for machining the edge areas of plate-shaped objects, such as, for example, glass panes or the like, for which the grinding wheels, in a conditioned state, have at least one circumferential groove each which, at least in a partial section, tapers off towards the grinding wheel center, and for the conditioning of which the conditioning device has a cross section which is adapted to the cross section of the groove to be achieved and in that the width of the conditioning device basically corresponds to the width of the groove(s) and in that the length orientation from one lateral end to the other lateral end of the conditioning device can be configured in accordance with the depth orientation from one side edge to the other side edge of the groove(s) with growing length at an increasing depth to be achieved. This means that the rotating grinding wheel can be conditioned by contact with the bar-shaped conditioning device, while the grinding wheel can remain in the clamping fixture of the grinding equipment. In addition, the width of the conditioning device can be smaller than the groove, through which, however, only partial sections of the groove will be conditioned. On the other hand, the width of the conditioning device can also be larger than the width of the groove, through which the projecting sections will be removed unused.
Sharpening and, if required, profiling of the grinding wheel is effected automatically, at longest possible profile-maintenance, by the specially configured cross section of the conditioning device as the material removal depends on the length engaged in the grinding operation and the length orientation of the conditioning device corresponds to the depth orientation of the groove. Consequently, with the extreme, tapered side edges of the conditioning device, thus having a length of approximately zero, practically no material is removed while with the central areas of the conditioning device, having a longer length, a stronger removal is achieved resulting in the corresponding groove depth at this point.
Also, the width of the conditioning device can basically correspond to the width of the groove(s) and the volume orientation over the width of the conditioning device can be configured in accordance with the depth orientation from one side edge to the other side edge of the groove(s) with growing volume at increasing depth to be achieved, so that by variation of the number and size of incorporated pores or, especially of the clearances configured as lateral grooves or the like, a more or less strong conditioning is achieved.
In addition, the width of the conditioning device can basically correspond to the width of the groove(s) and the abrasive properties of the material of the conditioning device over the width of the conditioning device can be configured in accordance with the depth orientation from one side edge to the other side edge of the groove(s) with better abrasive properties at increasing depth to be achieved.
Furthermore, according to the invention, also the width of the conditioning device can basically correspond to the width of the groove(s) and the adjustment of the grain size distribution in relation to the chip clearances of the grinding wheel over the width of the conditioning device can be configured in accordance with the depth orientation from one side edge to the other side edge of the groove(s) with a better adaptation at increasing depth to be achieved, so that a stronger removal or better sharpening influence of the deeper groove is achieved.
The conditioning device can, in particular, have a bar-shaped form and during the operation it can be subjected to a translatory feed in the direction of its longitudinal axis according to the wear. But also other forms, such as, for example, a semicircular disc-shaped configuration or the like are possible, in that the cross section is configured as described above and that it is constant in direction of the feed.
Preferably, the cross section of the conditioning device or the section of the conditioning device engaged in the conditioning, respectively, can have a more or less triangular shape so that the desired groove form can be achieved with an easily generated geometrical form.
In addition, the cross section of the conditioning device or the section of the conditioning device engaged in the conditioning, respectively, can have a more or less rhomboidal shape so that with equal length orientation a less tapered cross section is achieved which, in axially symmetrical confirguration, can be used for conditioning irrespective of the machining equipment applied.
According to the invention the conditioning device can be composed of a multitude of part components encompassed by a fixing attachment so that based on the layout of the part components it is possible to adjust the contour of the conditioning device in or outside the action zone so that the contour of the groove to be achieved can be selected. This permits the machining and conditioning of multiple groove forms and widths with a single conditioning device.
The part components can be composed of materials with different material properties so that a further influence of the grinding wheel groove to be achieved by the conditioning device can be obtained by variation of the material of the part components.
It can be advantageous to use a conditioning device made of a mineral material with a hardness and abrasive effect suitable for the conditioning of the grinding wheel.
Furthermore, the invention relates to a method for the conditioning of grinding wheels for machining the edge areas of plate-shaped objects, such as, for example, glass panes or the like, for which the grinding wheels, in a conditioned state, have at least one circumferential groove each which, at least in a partial section, tapers off towards the grinding wheel center.
The aforementioned disadvantages are avoided by a method for the conditioning of grinding wheels for machining the edge areas of plate-shaped objects, such as, for example, glass panes or the like, for which the grinding wheels, in a conditioned state, have at least one circumferential groove each which, at least in a partial section, tapers off towards the grinding wheel center, by means of a conditioning device of the before described type, wherein the conditioning device is brought into engagement with the rotating grinding wheel and advanced according to the material removal.
The advancement can be carried out manually or by machine, especially automatically by spring force or controlled by motor-operated drive.